Non-monotone DR-submodular Maximization is closely related to non-monotone submodular set function maximization because the algorithm for the latter problem can be applied to the former problem directly. The non-monotone submodular maximization is also called Unconstrained Submodular Maximization(USM). USM has various applications, such as marketing strategies over social networks [1]}, Max-Cut[2]}, and maximum facility location [3]}. USM problem has been studied extensively[4]}, [5]}, [6]}. Buchbinder gives a tight linear time randomized (1/2)-approximation for the problem[7]}.
